If you had a honey badger, it probably wouldn't care.http://www.youtube.com/watch?v=-qsclhKhAss
On a more serious note, you could try splitting the air condition outlet in two parts; one for the animal, and one for the miner. You may have to use small fans in front of the duct to pull the cool air through the tubes, but for even a small AC unit it could work. I think ferrets tend to be more warm blooded than humans, so any body of even lukewarm water could help them chill off. That's my 0,02 btc, hope it helps! Good luck!
Ferrets, from what I've read, don't like to be much hotter than 80 degrees. I am not trying to scold you, but a -lot- of people get ferrets with a terrible lack of knowledge concerning them. Ferrets are much happier in pairs, they need lots of space, attention, love, and possibly the most commonly overlooked detail of concerning ferrets is what they eat. Several of the ferrets I've come across were handled poorly, it is a shame. Plenty of ferrets love to snorkel. They don't actually have a snorkel on, they just submerge their upper body into the water and move their head around. They prefer clean water though, in a glass dish.
Obviously, heat management is an important detail concerning most electronics. If you are serious about mining and the well being of your ferret, I recommend putting together a sort of box or trap for the heat.
I am thinking cardboard (for cost and something that someone with an apartment could probably put together). Using lots of duct tape, a few well placed holes in the box setup, and the boxes venting straight out the window with it all sealed up and a few fans sucking the air out of the box, you'd have a fair amount of isolation going on without heating up the contents of the box.
The most simple and obvious solution is (as I am trying to draw for you) is to vent the heat to the outside.